Toured to West Deso through Powder Park 3. Cold with light winds at the ridge with new snow not effected by the wind. Started down skier's left of the cliff bands and with no effort caused multiple sluff avalanches that morphed into a bigger one about 100 ft wide and ran about 300 feet. This entrained the top 4 inches of snow and picked up considerable speed before stopping as the angle lessened. Could have easily carried a person. This run seemed to be the only area that had a high enough slope angle to allow the sluff to run.